Re: [MdeModulePkg/TerminalDxe] Why do we delay 2s for ESC being pressed?

[Heyi Guo <heyi.guo@linaro.org>]

That makes sense. Thanks very much for your explanation.

Regards,

Heyi


在 11/8/2017 4:46 PM, Ni, Ruiyu 写道:
> Yes. 2 seconds is for some other terminal tools, that cannot do the F10 translation.
>
> Thanks/Ray
>
>> -----Original Message-----
>> From: Heyi Guo [mailto:heyi.guo@linaro.org]
>> Sent: Wednesday, November 8, 2017 4:45 PM
>> To: Ni, Ruiyu <ruiyu.ni@intel.com>; Zeng, Star <star.zeng@intel.com>; edk2-
>> devel@lists.01.org
>> Cc: Dong, Eric <eric.dong@intel.com>
>> Subject: Re: [MdeModulePkg/TerminalDxe] Why do we delay 2s for ESC
>> being pressed?
>>
>>
>>
>> 在 11/8/2017 4:34 PM, Ni, Ruiyu 写道:
>>> No.
>>> Even a terminal tool can recognize F10, it still needs to translate it into "ESC
>> [ V"
>>> and send the three bytes to firmware.
>> Got it. But the 2 seconds timeout is not for this situation, right? If terminal
>> tool could translate and send the key sequence, I think it can complete 3
>> bytes transfer in a very short time, isn't it? E.g. 9600 baud / 8 = 1200 Bytes/s
>> (ignore control bits).
>>
>> So 2 seconds timeout is still for user to enter the sequence "ESC [ V"
>> manually?
>>
>> Thanks,
>>
>> Heyi
>>
>>> Thanks/Ray
>>>
>>>> -----Original Message-----
>>>> From: Heyi Guo [mailto:heyi.guo@linaro.org]
>>>> Sent: Wednesday, November 8, 2017 4:31 PM
>>>> To: Ni, Ruiyu <ruiyu.ni@intel.com>; Zeng, Star <star.zeng@intel.com>;
>>>> edk2- devel@lists.01.org
>>>> Cc: Dong, Eric <eric.dong@intel.com>
>>>> Subject: Re: [MdeModulePkg/TerminalDxe] Why do we delay 2s for ESC
>>>> being pressed?
>>>>
>>>>
>>>>
>>>> 在 11/8/2017 3:55 PM, Ni, Ruiyu 写道:
>>>>> Heyi,
>>>>>
>>>>> If you check the comments below in TerminalConIn.c:
>>>>>
>> https://github.com/tianocore/edk2/blob/master/MdeModulePkg/Universal
>>>> /C
>>>>> onsole/TerminalDxe/TerminalConIn.c#L1319
>>>>>
>>>>> TerminalDxe driver needs to determine whether user wants to press
>>>>> ESC alone, or press "ESC [ V" for F10 (PCANSI terminal).
>>>> Do you mean F10 is not directly supported on some terminal tools so
>>>> that we need to press 3 keys "ESC [ V" quickly and continuously to
>> emulate F10?
>>>> Thanks,
>>>>
>>>> Heyi
>>>>> So a 2 second timeout is added to wait additional keys.
>>>>>
>>>>> Thanks/Ray
>>>>>
>>>>>> -----Original Message-----
>>>>>> From: Zeng, Star
>>>>>> Sent: Wednesday, November 8, 2017 3:25 PM
>>>>>> To: Heyi Guo <heyi.guo@linaro.org>; edk2-devel@lists.01.org
>>>>>> Cc: Ni, Ruiyu <ruiyu.ni@intel.com>; Dong, Eric
>>>>>> <eric.dong@intel.com>; Zeng, Star <star.zeng@intel.com>
>>>>>> Subject: RE: [MdeModulePkg/TerminalDxe] Why do we delay 2s for
>> ESC
>>>>>> being pressed?
>>>>>>
>>>>>> Cc Terminal expert Ray to see if any comments on this.
>>>>>>
>>>>>>
>>>>>> Thanks,
>>>>>> Star
>>>>>> -----Original Message-----
>>>>>> From: Heyi Guo [mailto:heyi.guo@linaro.org]
>>>>>> Sent: Wednesday, November 8, 2017 3:04 PM
>>>>>> To: edk2-devel@lists.01.org
>>>>>> Cc: Zeng, Star <star.zeng@intel.com>; Dong, Eric
>>>>>> <eric.dong@intel.com>
>>>>>> Subject: [MdeModulePkg/TerminalDxe] Why do we delay 2s for ESC
>>>> being
>>>>>> pressed?
>>>>>>
>>>>>> Hi folks,
>>>>>>
>>>>>> We found ESC key responded fairly slow on serial port terminal, and
>>>>>> we think it might be caused by the code in UnicodeToEfiKey in
>>>> TerminalConIn.c:
>>>>>>         if (UnicodeChar == ESC) {
>>>>>>           TerminalDevice->InputState = INPUT_STATE_ESC;
>>>>>>         }
>>>>>>
>>>>>>         if (UnicodeChar == CSI) {
>>>>>>           TerminalDevice->InputState = INPUT_STATE_CSI;
>>>>>>         }
>>>>>>
>>>>>>         if (TerminalDevice->InputState != INPUT_STATE_DEFAULT) {
>>>>>>           Status = gBS->SetTimer(
>>>>>>                           TerminalDevice->TwoSecondTimeOut,
>>>>>>                           TimerRelative,
>>>>>>                           (UINT64)20000000
>>>>>>                           );
>>>>>>           ASSERT_EFI_ERROR (Status);
>>>>>>           continue;
>>>>>>         }
>>>>>>
>>>>>> It seems we intentionally add 2 seconds delay for ESC key press.
>>>>>> This provides not so good user experience when we press ESC to exit
>>>>>> or cancel some operation.
>>>>>>
>>>>>> We tried reducing this timeout value to 1 second, then the
>>>>>> experience improved much and we didn't find any issue introduced.
>>>>>>
>>>>>> What's the reason for this timeout value and is there any improvement?
>>>>>>
>>>>>> Thanks and regards,
>>>>>>
>>>>>> Heyi